New dyestuffs



United States Patent Qfifi f 3,057,871 Patented Oct. 9, 1932 6 71, NEWDYESTUFFS Eduard Moser, Basel, Switzerland, assignor to Ciba Limited,Basel, Switzerland, 21 company of Switzerland N0 Drawing. Filed Nov. 21,1960, Ser. No. 70,375

Claims priority, application Switzerland Nov. 23, 1959 6 Claims. (Cl.260'295) This invention provides dyestutls of the general formula inwhich R R R and R each represent a hydrogen atom or a substituent notimparting solubility in water and any two of which substituents inortho-position relatively to one another may together with the vicinalcarbon atoms of the basic structure form a ring m, n, p and q eachrepresent the whole number 1 or 2, and B represents a benzene radicalfree from groups imparting solubility in water.

The invention also provides a process for the manufacmm of the dyestuffsof the above general Formula 1, wherein two molecular proportions of ahalide of a 2:3- phthaloyl-pyrrocoline-l-carboxylic acid of the formula(the numbering of the pyrrocoline ring is that given in Pattersons ringindex) in which R R R R m, n, p and q have the meanings given above, arecondensed with one molecular proportion of a diaminobenzene free fromacid groups imparting solubility in water.

In the phthaloyl-pyrrocoline carboxylic acids of the Formula 2 R and Reach advantageously represent a hydrogen atom or a simple substitu'ent,such as a halogen atom or" a lower alkyl' group, R and R may, togetherwith the vicinal carbon atoms of the pyridine ring, form an alicyclic,heterocyclic of aromatic ring. R and R advantageously represent hydrogenatoms, but may represent halogen atoms, for example, chlorine or bromineatoms.

The 2:3-phthaloyl pyrrocoline c'arboxylic acids of the Formula 2 can beobtained, for example, by the process described in United States PatentNo. 2,877,230 patented March 10, 1959', to Robert S. Long et al. bycondensing a 2:3-dichloronaphthoquinone with an aCet'o-atic acid alkylester and pyridine or a substitution product thereof, for example,zx-picoline, and hydrolyzing the alkyl ester so obtained to the freecarboxylic acid. As a suitable naphthoquinone there may be mentionedmore especially, owing to the ease with which it can be obtained, 2:3-dichloronaphthoquinone itself. Alternatively, there may be used 2:3:5-or 2:3:6-trichloronaphthoquinone, 2 :3-dibromonaphthoquinone or 2 3 6 27-tetrabromonaphthaquinone.

There are advantageously used the chlorides of the 2:3-phthaloyl-pyrrocoline carboxylic acids. These chlorides can be obtainedfrom the carboxylic acids in known manner by treating the latter with anacid-chlorinating agent for example, phosphorus trichloride, phosphoruspentachloride or phosphorus oxychloride, but more especially thionylchloride.

The treatment with such acid-halogenating agents is advantageouslycarried out in an inert organic solvent such as dimethyl-formamide, achlorobenzene, for ex-' ample monochloroor dichlorobenzene, toluene,xylene or nitrobenzene. When the last mentioned solvent is used thereaction can be accelerated by a small proportion ofdimethyl-for'mami'de.

In making the carboxylic acid halides it is of advantage first to drythe carboxylic acid which has been produced in an aqueous medium or tofree it from Water by subjecting it to azeotropic boiling in an organicsolvent. This az'eotropic drying may be carried out immediately beforethe treatment with the acid-halogenat'ing agent.

As diamino-benzenes there may be used, for example,meta-diaminobenzenes, or more especially para-diaminobenZe'nes of theformula in which X and Y each represent a halogen atom, are drogen atomor a lower alkyl or alkoxy group or a nitro' group. As examples theremay be mentioned:

The condensation of the phthaloyl-pyrrocoline carboxylic acid halideswith the diamines is advantageously carried out in an anhydrous medium.Under these conditions the condensation generally takes placesurprisingly easily at temperatures within the boiling range of ordinaryorganic solvents, such as toluene, monochlorobenzene, dichlorobenzene,trichlorobenzene, nitrobenzene and the like. In order to accelerate thereaction an acid-binding agent, such as anhydrous sodium acetate,pyridine or anhydrous ammonia, may be used. The dyestutfs are generallyobtained in very good yield and in a pure state. It may be of advantagein order to obtain especially pure dyestutfs to separate the acidchloride obtained from the carboxylic acid and, if desired, torecrystallize it. In most cases, especially when thionyl chloride isused as acid-chlorinating agent, it is possible without harm, and evenin some cases with better results, to dispense with separation of theacid chloride and to carry out the condensation in the reaction mixturein which the acid chloride has been formed.

The dyestuffs of this invention can be used for dyeing a very widevariety of materials, for example, as vat dyestuffs for dyeing cellulosefibers or animal fibers, such as wool or silk, or synthetic fibers, suchas polyarnide, or polyester fibers. The dyestuifs may also be sulfonatedand used in that condition for dyeing the aforesaid fibers. Furthermore,the dyestuffs are suitable for all purposes for which pigments are used,for example, for so-called pigment printing, that is to say, the methodof printing in which a pigment is fixed on a substratum, especially on atextile fiber, or on another sheet-like structure, such as paper, forexample, wallpaper, or a fabric of glass fibers by means of an adhesive,such as casein, a hardenable synthetic resin, especially aurea-formaldehyde or melamine-formaldehyde condensation product, or asolution or emulsion of polyvinyl chloride or polyvinyl acetate or otheremulsion, for example, an oil-inwater or water-in-oil emulsion. Thepigments can also be used for other purposes, for example, in the finelydivided form for dyeing fibers of viscose or cellulose ethers or estersor fibers of polyamides or polyurethanes or polyacrylonitrile in thespinning composition. They are also suitable for coloring lacquers orlacquer formers, solutions or products or acetyl-cellulose,nitro-cellulose, natural substances of high molecular weight, such asgums, casein or synthetic resins, such as polymerization resins, forexample polyvinyl chloride, polyethylene, polypropylene or polystyrene,or condensation resins, for example, aminoplasts, phenoplasts, orsilicones or silicone resins. They can also be used with advantage inthe manufacture of colored pencils, cosmetic preparations or laminatedsheets.

Owing to their chemical inertness and good resistance to heat thepigments of this invention can be dispersed in the usual manner incompositions or products of the kind mentioned above, and this isadvantageously carried out at a stage in which such compositions orproducts have not been brought into the final form. The pigments can beconverted into a finely subdivided form by the known conditioningmethods. Operations required for shaping, such as spinning, pressing,hardening, casting, sticking or the like can then be carried out in thepresence of the pigments.

The pigments are distinguished by their excellent fastness to light andmigration.

The following examples illustrate the invention, the parts andpercentages being by weight unless otherwise stated, and therelationship of parts by weight to parts by volume being the same asthat of the kilogram to the liter:

Example 1 30.9 parts of 2:3-phthaloylpyrrocoline-carboxylic acidchloride of the formula prepared as described in US. Patent 2,877,230patented March 10, 1959, to Robert S. Long et al. by heating 2:3-dichloroor 2:3-dibromonaphthoquinone, aceto-acetic acid ester andpyridine, hydrolyzing the resulting 2:3-phthaloylpyrrocoline-1-carboxylic acid ethyl ester to form thecarboxylic acid and reacting the latter with thionyl chloridearesuspended at C. in 750 parts of an hydrous ortho-dichlorobenzene; afterabout 20 minutes a clear solution is obtained into which in the courseof about 5 minutes is poured a solution heated at C. of 7.2 parts of2-chloro-1:4-diaminobenzene in 150 parts of anhydrousortho-dichloro-benzene and 2.5 parts of anhydrous pyridine. The whole isheated to 140 to 145 C. and maintained at that temperature for 4 hours,after which it is allowed to cool to 100 C., filtered, and the resultingpigment is washed with ortho-dichlorobenzene heated at 100 C. until thesolvent runs 01f substantially colorless. The product is then washedwith a small amount of cold methanol and then with hot water. The redpigment is dried in vacuo at 90 to 100 C. When used for coloringpolyvinyl chloride foils it produces a bluish red coloration ofexcellent fastness to migration and light. The pigment dissolves inconcentrated sulfuric acid with blue coloration and dyes cellulosefibers from the vat bluish red tints of good fastness to light andwetting.

When 2-chloro-1:4-diaminobenzene is replaced by an equivalent amount of2:5-dichloro-1:4-diaminobenzene, and the resulting pigment is used forcoloring polyvinyl chloride foils, a pure red tint is obtained, while2:5-dibromo-l:4-diamino-benzene produces a scarlet tint, 1:3-dibromo-4:6-diaminobenzene a claret tint, 2-chloro-5-methyl-1:4-diaminobenzene a claret tint, 2:5-dimethoxy-1:4-diaminobenzene a brown tint, 2:5-diethoxy-lz4-diaminobenzene ayellowish brown tint, and 1:4-diamino- Z-nitrobenzene a reddish browntint.

All aforementioned colorations are of excellent fastness to migrationand light.

Example 2 A suspension of 29.1 parts of 1:2-phthaloylpyrrocoline-3-carboxylic acid of the formula COOH in 750 parts of anhydrousortho-dichlorobenzene and 14.8 parts of thionyl chloride is heatedwithin about 40 minutes to C. and maintained for 2 hours at 130 to C.The resulting solution of the acid chloride is treated within 5 minuteswith a solution heated at 120 C. of 7.2 parts of2-chloro-1:4-diaminobenzene in 150 parts of anhydrousortho-dichlorobenzene and 2.5 parts of anhydrous pyridine. The reactionmixture is heated to C. and maintained at that temperature for about 10hours, then allowed to cool to 100 C., and the precipitated pigment isfiltered off and washed with orthodichlorobenzene heated at 100 C. untilthe washing liquor runs substantially colorless. 'Ihe filter residue is5 then washed with a small amount of methanol and then with hot water.The pigment is dried in vacuo at 90 to 100 C. The properties of thepigment so obtained correspond to those of the pigment prepared asdescribed in Example 1.

Example 3 34.4 parts of 4 or 5'-chloro-1:Z-phthaloylpyrrocoline-3-carboxy1ic acid chloride of the formula melting at 206 to 212 C.,uncorrected, with decomposition-prepared from 2:3 6-trichloro-1:4-naphthoquinone with acetoacetic acid ethyl ester and pyridine,followed by hydrolysis to yield the free carboxylic acid and forming itsacid chloride with thionyl chlorideare condensed with 8.85 parts of2:5-dich'loro-l:4-di'aminobenzene as described in Example 1. Theresulting pigment colors polyvinyl chloride foils claret shades havinggood fastness to migration and light, and cellulose fibers from the vatclaret shades having good fastness to light and wetting.

When 2:5-dichloro-l:4-diaminobenzene is replaced by an equivalent amountof 1:4-diaminobenzene, there are obtained in polyvinyl chloride foils ablue shade and on cotton from the vat a bluish violet shade. Coloringwith 2-chloro-1:4-diaminobenzene produces a violet shade, with2:5-diethoxy-1:4-diaminobenzene an olive shade, with2-chloro-5-methyl-1:4-diaminobenzene a violet shade, with2:5-dimethyl-l:4-diaminobenzene a reddish blue shade, and with 2:5dibromo-l:4-diaminobenzene a bluish red shade.

All colorations in polyvinyl chloride possess good fastness to migrationand light and the vat dyein'gs possess good fastness to light andwetting.

Example 4 When the acid chloride is prepared from 32.6 parts of 4- or5-chloro-2:3-phthaloylpyrrocoline-l-carboxylic acid of the formula COOHas described in Example 2 and condensed as stated with 8.85 parts of2:5-dichloro-1:4-diaminobenzene, the resulting pigment possessesproperties identical with those of the pigment described in Example 3.

Example 65 parts of polyvinyl chloride, 35 parts of dioctylphthalate and0.2 part of the pigment prepared as described in Example 1, paragraph 1,are stirred together and rolled to-and-fro on a two-roller calender for7 minutes at 145 C. The resulting red foil displays good fastness tolight and migration. When in addition to the dyestufi. pigment mentionedabove there are used 5 parts of titanium dioxide, a red pastel shade isobtained.

Example 6 0.25 part of the dyestuif as claimed in Example 1 are groundfor 24 hours in a rod mill with 40 parts of an alkydmelamine stovinglacquer containing 50% of solids, and

6 r with 4.75 parts of titanium dioxide. A thin coating of the resultinglacquer is brushed on an aluminum foil and stoved for one hour at C. Ared lacquer coating of good fastness light is obtained.

Example 7 For the manufacture of a laminate the following componentlayers are prepared:

(a) Strong paper of unbleached. sulfate cellulose (socalled kraft paper)is impregnated with an aqueous phenol-formaldehyde resin solution,pressed and dried.

(1)) Paper of pure, chemically bleached cellulose containing zincsulfide or titanium dioxide as filler is impreg nated with an aqueoussolution of dimethylolmelamine of 50% strength, pressed and dried at 100C.

'(c) 400 parts of a fancy paper of bleached cellulose containing zincsulfide or titanium dioxide as filler are disintegrated in a hollanderwith 10,000 parts of water, 30 parts of the pigment prepared asdescribed in Example 1 are added to the paper pulp so obtained. Thepigment is fixed by adding 16 parts of aluminum sulfate. The dyed fancypaper is impregnated with an aqueous solution of dimethylolmelamine of50% strength, pressed and dried at 100 C.

(d) According to the quality of the laminate the fancy paper isprotected with tissue paper of bleached special cellulose, weighing 40grams per square meter. The tissue paper is likewise impregnated with anaqueous solution of dimethylolmelamine of 50% strength, pressed anddried at 100 C.

A sandwich is prepared from the papers thus treated, each measuring, forexample, 2.75 m. by 1.25 m., in the following order: First 3 to 5 sheetsof paper (a), one sheet of paper (b), one sheet of paper (c) and ifdesired one sheet of paper (d), and the sandwich is compressed betweenmirror-chromed plates for 12 minutes at to C. under a pressure of 100'kg. per sq. cm. The sandwich is then cooled to 30 C. and removed fromthe press, whereupon it displays on one side a bluish red shade havingvery good fastness to light.

Example 8 1 part of the dyestuff obtained as described in Example 1 from2:5-dichloro-l:4-diaminobenzene is v'att'ed in 100 parts of watercontaining 4 parts by volume of sodium hydroxide solution of 30%strength with 2 parts of sodium hydrosulfite at 45 C. The resultingstock vat is added to a solution of 4 parts by volume of sodiumhydroxide solution of 30% strength and 2 parts of sodium hydrosulfite in2000 parts of water. In the resulting dyebath 100 parts of cotton aredyed for one hour at 25 to 30 C. with addition of 20 parts of sodiumchloride. The cotton is then squeezed, oxidized in air, rinsed,acidified, again rinsed and soaped at the boil. A bluish red dyeing isobtained which has excellent fastness to light and wetting.

What is claimed is:

1. A dyestuif of the formula 7 v 8 2. The dyestufi of the formula 4. Thedyestufi of the formula 0 O y o l N 5 N u l 01 1 NO: I -coNH NH00-(l INHOO-C--- I 0 (51 0 1O 0 5. The dyestufi of the formula 6. The dyestufiof the formula 3. The dyestufi of the formula References Cited in thefile of this patent m I 7 UNITED STATES PATENTS O I f 2,772,274Schmidt-Nickels et a1. Nov. 27, 1956 N 01 N 2,773,873 Randall et a1.Dec. 11, 1956 i I l i 2,877,230 Long et a1 Mar. 10, 1959 OONH NHOC- 45OTHER REFERENCES l H H Noller: Chemistry of Organic Compounds (1957), p.

0 0 549 (Saunders).

1. A DYESTUFF OF THE FORMULA